Retinoid-induced ear malformations

Treatment of pregnant Sprague-Dawley rats with retinoic acid or etretinate pregnancy day 8.5 to 9.0 resulted in craniofacial defects in 100% of the embryos. A morphologic investigation of the malformations occurring in the ear was performed. Outer ears were missing, microtic, low-placed, and dorsally situated. External acoustic meatus was short or absent. Middle ear structures were delayed in differentiation, middle ear ossicle primordia were hypoplastic and malformed, the stapedial artery and facial nerve were hypoplastic, and their relation to the stapes was variable. In the inner ear, the otic capsule was thick, the cochlea had fewer turns and the semicircular ducts showed poor differentiation.

Unilateral duplication of the cerebellar hemisphere and internal, middle, and external ear: a clinical case study

This article presents the unique congenital anomaly complex of ipsilateral cerebellar hemisphere duplication and internal, middle, and external ear duplication. Diagnostic techniques included a head CT scan, a three-dimensional head CT scan, and a head MRI. An aberrant notochordal split was proposed as the embryologic mechanism leading to the development of such anomalies.

Right-sided microtia and conductive hearing loss with variable expressivity in three generations

Familial cases of microtia and meatal atresia are rare, and both dominant and recessive inheritance have been suggested. We here report a family with right-sided external ear malformations and conductive hearing loss in a grandfather, his daughter and granddaughter. The grandfather and the granddaughter both had microtia and meatal atresia, whereas the daughter had a normal outer ear except for a narrow meatus and auricular appendages. The pedigree suggests autosomal dominant inheritance with variable expressivity.

[Improved inner ear diagnosis by controlled use of computerized tomography]

Problems in the examination of the inner ear using conventional CT are described. Intraoperative findings often differ from CT findings. A new development HR-CT is introduced. Findings of middle and inner ear malformations and otosclerosis are demonstrated. It is shown that HR-CT imaging using a new 1024 matrix, enables better spatial resolution. This new CT technique improves inner ear examination, especially in the preparation for cochlear implantation.

Congenital malformations of the external, middle, and inner ear produced by isotretinoin exposure in mouse embryos

Isotretinoin (Accutane), a widely used dermatologic drug, produces severe congenital malformations when used during pregnancy. The isotretinoin teratogen syndrome consists of multiple cardiovascular and craniofacial anomalies, most commonly involving the external ear. This study examined the pathogenesis of isotretinoin teratogenicity in a mouse model, using microdissection and histologic examination of fetal mouse ears after treatment with the drug at various stages of embryonic development. In this study, earlier treatment times frequently produced microtia similar to that seen in affected infants, as well as recognizable patterns of temporal bone and ossicular abnormalities; exposure at a later developmental stage resulted in facial tags with less severely affected ears. Possible teratogenic mechanisms of isotretinoin are discussed. Suitability of the mouse model for studying human congenital craniofacial malformations, such as Goldenhar's and Treacher Collins Syndrome, is also explored.

One-stage total reconstruction of the ear with simultaneous tympanoplasty

The one-stage total ear reconstruction (auricular reconstruction and tympanoplasty) has a number of merits. 1. Satisfactory esthetic results obtained in one operation. 2. The "super thin" skin flap is elevated on a plane that excludes hair follicles from the flap, so the hair-bearing areas of the scalp can be readily incorporated as part of the ear reconstruction. 3. The reconstructed ear has adequate blood supply and protective sensation. 4. The surgeon may choose to carry out a tympanoplasty and obtain restoration of auditory function or may choose to carry out a pseudomeatus procedure and reduce the operating time. We feel that the "super thin" skin flap and the simultaneous tympanoplasty are valuable supplements to ear reconstruction. The functional results of the tympanoplasty must be considered only a partial success at this time; long-term evaluation as well as technologic improvements are needed.

Temporal bone histopathologic findings in Alagille's syndrome

Six temporal bones obtained from four individuals with Alagille's syndrome, aged 4 months and 3, 6, and 7 years, were studied histopathologically. The external auditory canals and tympanic membranes were normal. Although the stapes, the interossicular joints, and the subarcuate fossae were slightly underdeveloped in the majority of cases, the other structures in the middle ear were almost normal. However, severe anomalies were observed in structures in the inner ear. In all cases, both the bony and membranous structures of the posterior semicircular canal were partially or totally absent, and, in three ears, those of the anterior semicircular canal were also partially absent; the lateral semicircular canal, however, was normal in all cases. The cochlea was observed to be shortened in only one case.

Perilymphatic fistula in pediatric patients with a preexisting sensorineural loss

A specific group of 28 children (38 ears) with a preexisting sensorineural hearing loss (SNHL) was studied to determine if a perilymphatic fistula (PLF) was the cause of a progression in their hearing loss. A PLF was identified surgically in six of these ears, but there was no evidence of any defect found in 32 ears. The symptoms shared by the cases in which a fistula was found included a traumatic event (including exertion), CT scan evidence of inner ear defects, hearing threshold decreases of 25 to 30 dB, and vertigo or postural instability.

Congenital perilymphatic fistula: an overlooked diagnosis?

Congenital perilymphatic fistula (CPLF) often is the sole cause of sensorineural hearing loss in children that is both progressive and subtle and, therefore, can elude detection by physicians. A 3-year prospective study of 244 children with sensorineural hearing loss of unknown etiology demonstrated that at least 6% (15/244) had CPLF. Close audiologic monitoring and radiologic imaging of the temporal bone of children with sensorineural hearing loss are recommended to detect CPLF.

External and middle ear malformations: autosomal dominant genetic transmission

Congenital malformations of the external and middle ear relatively frequent anomalies (one to five cases in 20,000 live births). They are part of genetic syndromes such as Treacher Collins and Goldenhar's syndromes, but most cases are isolated and sporadic. A few cases of familial incidence of isolated external and middle ear malformations with autosomal recessive, autosomal dominant, and sex-linked modes of transmission have been described. We report on two siblings with almost identical anomalies of the external and middle ear and no other congenital defects. Their father had similar malformations, but nobody else in his large sibship presented ear malformations. The defects were also absent in two previous generations. We discuss the possibility, not previously mentioned in the literature, that these congenital malformations could have appeared by spontaneous mutation in the father and transmitted themselves as an autosomal dominant trait to his children.

Treacher Collins syndrome: an otologic challenge

Patients with Treacher Collins syndrome have severe middle ear malformations that render operation difficult. We have evaluated 43 patients with Treacher Collins syndrome, on whom only 11 were operated. Computed tomography, the single most important study done preoperatively, routinely showed an underdeveloped temporal bone with islands of bone marrow and absent mastoid pneumatization. The middle ear space was often underdeveloped. Ossicular dysjunction was often noted in which the fused malleus/incus remnant was found 3 to 4 mm distant to the stapes. A common finding was severe dysplasia of the stapes-facial nerve complex that often made the middle ear malformation uncorrectable. Hearing results were much less predictable than in patients with isolated atresia/stenosis of the ear.

The relations of the mastoid segment of the facial canal to surrounding structures in congenital middle ear malformations

The authors investigated the relations between the mastoid segment of the facial canal and the temporomandibular joint, the posterior wall of the cavum tympani and the external wall of the mastoid process in 19 cases with congenital ear malformations and 10 cases with normal ears. A significantly reduced distance was found between the facial canal and the temporomandibular joint as well as between the facial canal and the posterior wall of the cavum tympani in the groups with malformed ears as compared to the control group with normal ears.

Congenital aural atresia

This report is based on 25 years' experience in the surgical management of 69 ears with congenital aural atresia. There were 7 ears with meatal atresia, 11 with partial atresia, 50 with total atresia, and 1 with hypopneumatic total atresia. Meatoplasty was performed in 7 ears, canaloplasty was performed in 22 ears, canaloplasties with strust in 8 ears, and mastoidectomy with stapediopexy was performed in 26 ears. Of the 62 ears that had partial or total atresia, five (8%) had hidden cholesteatomas that were destined to create future complications by expansion and erosion had they not been removed. In five of the 62 ears, temporary facial palsy resulted from exposing the facial nerve in the atresia plate, and in another five ears, attempts to improve hearing were abandoned intraoperatively because of surgically insurmountable anomalies. A reasonable criterion for success in an operation for bilateral atresia is that the need for a hearing aid is obviated; whereas, for unilateral atresia, a successful procedure should largely eliminate the disadvantages of unilateral hearing loss. These criteria seem to be satisfied if the threshold of hearing can be brought to a level of 20 dB or better. This criterion was met in 30% of the group that underwent canaloplasty and in 8% of the group that underwent mastoidectomy with stapediopexy.

[Relation between the level of involvement of the ear, the middle ear and the face in microtia]

Based on examination of 80 adult men with unilateral microtia the authors examined the relationship between the affection of the ear lobe, middle ear and face. The revealed significant relations were due solely to subjects with the most severe or with the slightest affection. Correlation coefficients therefore do not characterize relations in the majority of patients and their magnitude is influenced by the ratio of marginal variants of the anomaly in the group. The calculation of the relationship for the entire range of variation of the defect thus is useless. These findings may have a more general validity. They are consistent with the experimental evidence on a haematogenic origin of branchiogenic defects and assumptions derived from this hypothesis. Facial asymmetry is a prognostically important sign for the estimation of the extent of damage of the middle ear.

[The value of high-resolution computerized tomography in abnormalities of the middle ear]

Middle ear malformations are common congenital disorders of the head and neck area. Recent advances in plastic and middle ear surgery have improved the prognosis of patients suffering from congenital hearing disorders. However, sophisticated preoperative procedures are mandatory. The development of HR-CT has improved the radiologic possibilities to evaluate middle ear disorders significantly. In the present study we examined by means of HR-CT twenty patients with congenital middle ear malformation. Our findings include different sizes of the middle ear as well as dysplastic alterations of the malleus and incus. The inner ear was normal in almost all cases. Our results indicate that preoperative HR-CT is a reliable diagnostic method to demonstrate middle ear disorders.

[Aberrant internal carotid artery in the middle ear]

An aberrant internal carotid artery in the middle ear is rare. We present a new case with a red mass behind the eardrum. The diagnosis must be established by radiology and angiography. The consequences of injury and surgical intervention are serious. The purpose of this paper is to review the literature on the subject of vascular anomalies of the middle ear and to discuss the diagnosis and management of this lesion.

Spontaneous cerebrospinal fluid otorrhea in a deaf infant

Spontaneous (congenital) cerebrospinal fluid (CSF) otorrhea is a rare occurrence with less than 100 cases being reported in the literature. In infants and children, it may present as otitis media with effusion. A 4-month-old infant, who was diagnosed with severe to profound sensorineural hearing impairment and spontaneous CSF otorrhea, initially presented with otitis media with effusion. The patient presentation, diagnostic dilemmas and pathophysiology of this rare but interesting problem are discussed.

[Radiodiagnosis of temporal bone anomalies]

The X-ray findings in temporal bone anomalies are reviewed. Radiological procedure and examination technique are presented, as are symptoms of important anomalies. The methods available are plain film X-ray of temporal bone, multi-directional tomography, and high-resolution CT. Although some of the abnormalities are visible even in plain films, consistent use of conventional tomography or CT is necessary for correct diagnosis. This procedure is indicated not only when an abnormality is clinically obvious, but also in all cases of unexplained hearing loss without evidence of acquired disease. The advantage of CT over conventional tomography is that soft tissue anomalies, such as primary cholesteatoma or tumor simulating vascular abnormalities, can be demonstrated. In these cases CT is obligatory.

Frequency and localization of congenital anomalies of the middle and inner ears: a human temporal bone histopathological study

This study investigated congenital anomalies occurring in the middle and the inner ears, with particular attention to their features, localizations, and frequencies. One hundred human temporal bones obtained from 73 individuals, aged 31 gestational weeks to 39 years, each of whom had anomalies of the middle ear and/or inner ear, were used for this study. The temporal bones had been removed at autopsy, fixed, dehydrated, embedded in celloidin, and sectioned horizontally or vertically at 20 microns. Every 10th horizontal section or every 20th vertical section was stained with hematoxylin and eosin, mounted and studied under a light microscope. In the middle ear the structure most often found to be anomalous was the facial nerve; in the inner ear it was the lateral semicircular canal. The implications of the anomalies observed are discussed as they relate to fetal development, dysfunction of the ear, and clinical interpretation of diagnostic radiological studies.

[Otologic signs and early diagnosis of Turner syndrome. Reevaluation of 30 cases]

In most occasions the Turner's syndrome is diagnosed on the basis of severe growth retardation. But the possibility of an effective treatment of short stature requires earlier a diagnosis. Among the other signs, the importance of ORL signs is underestimated. A group of 30 patients has been analysed to determine their precise extension. The external ears are frequently prominent, low-set and/or posteriorly rotated. Frequency and chronicity of otitis media is highlighted by hypoacousy of the transmission type. The perception pathology is far less common and seems being independent of middle ear pathology. A abnormal development of the 1st branchial arch is likely to explain the auricular pathology in view of the frequently associated anomalies of the palate and the dental articulation. One must clearly consider the diagnosis of Turner syndrome in the case of chronic auricular pathology associated with low linear velocity in a young girl allowing for earlier diagnosis.

Surgery of major congenital aural atresia

Accurate preoperative clinical, audiometric and radiographic evaluation is a prerequisite for surgery of major congenital aural atresia, which is accepted as one of the most difficult otological reconstructive procedures to perform. The main aim is to achieve serviceable hearing. Middle ear and facial nerve anomalies and functional results of eleven consecutive primary operations by one of the authors are presented. Familiarity with various Tympanoplastic and Facial nerve surgical techniques is mandatory.

Congenital malformations of the ear

Either CT or pluridirectional tomography is capable of demonstrating bony anomalies of the ear. For a variety of reasons, high-resolution "bone algorithm" CT is used as the first imaging procedure at our institution, and pluridirectional tomography is done only on rare occasion, usually when there is an ambiguity on the CT images.

Anomalies of the middle ear

Malformations of the ossicles in 52 ears of 48 patients were analyzed on the basis of surgical findings. The external meatus of each of these ears was patent. The long process of the incus and the stapes are frequently involved in this series of observations. There are distinct groups of ossicular anomalies, in each of which patients show similar degrees of hearing loss and ossicular findings. These include spindle handle, malleus bar, and dislocated annulus. Spindle handle gets its name from the shape of the malleus handle. There is disconnection between the long process of the incus and the capitulum of the stapes. Malleus bar is a kind of malleus fixation, in which a small bony bar connects the tip of the malleus handle to the posterior wall of the tympanic cavity. In the dislocated annulus, the annulus is dislocated cranially in relation to the middle-ear structures. Anomalies of the ossicle are usually present. Surgical repairs for these conditions are discussed.

Correlation between high-resolution computed tomography and surgical findings in congenital aural atresia

Congenital aural atresia poses a great challenge, even to a competent otologic surgeon, due to innumerable types of malformations affecting the conduction and perception of sound. Roentgenographic evaluation by plain roentgenography is inconclusive in most cases; polytomography is helping to some extent. Recent generations of high-resolution computed tomographic (CT) scanners are probably the best. Seven cases of unilateral and three cases of bilateral congenital aural atresia were evaluated with high-resolution CT. Subsequently, ten ears were operated on. Surgical findings were correlated with CT scan findings with respect to atresia plate, extent of pneumatization, ossicular anomalies, bony facial nerve canal, and inner ear. Use of CT scans bears considerable importance in the management of these types of cases. High-resolution CT scan, when targeted for maximal bony detail, is possibly the method of choice in congenital aural atresia when surgical correction is contemplated.